Chapter 8. Troubleshooting

Troubleshooting Guide

Table 8.1. Troubleshooting Guide

ProblemPossible CausesSolution
Signature Bytes read as 0x00 0x00 0x00ISP Frequency is to high.Lower ISP freq under the board settings
Not able to communicate with device through debugWIRERESET pullup resistor to smallRemove or increase the pull-up value to 10K ohm or more.
Not able to communicate with device through debugWIREDecoupling Capasitor destroys communication on RESET lineRemove Decoupling capasitor on reset line during debugWIRE emulation
debugWIRE communication fails when using STK500RESET line strongly tied to VCCRemove RESET jumper on STK500 to allow AVR Dragon to control the line.
After successfully enabling the DWEN fuse, AVR Dragon is not able to enter debug modeRESET line strongly tied to VCCRemove RESET jumper on STK500 to allow AVR Dragon to control the line.
Target voltage is read as 0V for on-board targets AVR Dragon get no reference voltage to the target voltage sensing. Target voltage is sensed from either pin 2 on ISP header or pin 4 on the JTAG header. In order to get reference voltage to the level converters of AVR Dragon, connect Pin 2 or 4 or 6 on the VCC header to pin 2 on ISP header or pin 4 on the JTAG header. Note that VCC pins on AVR Dragon are set to 5V and this procedure should therefore not be used for off-board targets.
Target voltage is read as 0V for off-board targets. AVR Dragon get no reference voltage to the target voltage sensing. Target voltage is sensed from either pin 2 on ISP header or pin 4 on the JTAG header. Connect the target voltage from the target board to pin 2 on ISP header or pin 4 on the JTAG header.
Not able to set ISP frequencyAVR Dragon is not reading any target voltage.See above
ISP/PP/HVSP programming failsAVR Dragon is not reading any target voltageSee above
Not able to connect to AVR Dragon, and status led is yellowAVR Dragon firmware upgrade failed, or firmware is corrupt.Go to the menu "Tools->Upgrade AVR Dragon" to perform a manual upgrade.